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Psychosocial interventions for infertile couples:A scoping review
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作者 Sreemol Sunil Anish K.R. 《Asian pacific Journal of Reproduction》 CAS 2024年第3期97-106,共10页
Objective:To bring out current evidence regarding psycho-social interventions for infertility care,and identify the best practices in clinical care.Methods:An in-depth literature review on infertility care interventio... Objective:To bring out current evidence regarding psycho-social interventions for infertility care,and identify the best practices in clinical care.Methods:An in-depth literature review on infertility care intervention was conducted using data from multiple databases:PubMed,EMBASE,Google Scholar,and PsycINFO.The relevant articles selected were between 2008 and 2022.Results:A literature search turned up 1798 citations,of which 25 studies were included after rigorous analysis.Various intervention categories have been constantly utilised to provide support and promote mental health,of which acceptance and commitment therapy(ACT)and cognitive behaviour therapy(CBT)were used most frequently.The interventions exhibited diversity in both content and composition,and addressed a wide range of issues.Conclusions:The review emphasizes that psycho-social interventions have a positive effect on psychological issues,relationships,and pregnancies among couples and can be incorporated into fertility-care practices. 展开更多
关键词 Infertile couples Psychosocial interventions Mental health Quality of life
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Influence of water coupling coefficient on the blasting effect of red sandstone specimens 被引量:1
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作者 Yang Li Renshu Yang +1 位作者 Yanbing Wang Dairui Fu 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第1期148-166,共19页
This study investigates the impact of different water coupling coefficients on the blasting effect of red sandstone.The analysis is based on the theories of detonation wave and elastic wave,focusing on the variation i... This study investigates the impact of different water coupling coefficients on the blasting effect of red sandstone.The analysis is based on the theories of detonation wave and elastic wave,focusing on the variation in wall pressure of the blasting holes.Using DDNP explosive as the explosive load,blasting tests were conducted on red sandstone specimens with four different water coupling coefficients:1.20,1.33,1.50,and 2.00.The study examines the morphologies of the rock specimens after blasting under these different water coupling coefficients.Additionally,the fractal dimensions of the surface cracks resulting from the blasting were calculated to provide a quantitative evaluation of the extent of rock damage.CT scanning and 3D reconstruction were performed on the post-blasting specimens to visually depict the extent of damage and fractures within the rock.Additionally,the volume fractal dimension and damage degree of the post-blasting specimens are calculated.The findings are then combined with numerical simulation to facilitate auxiliary analysis.The results demonstrate that an increase in the water coupling coefficient leads to a reduction in the peak pressure on the hole wall and the crushing zone,enabling more of the explosion energy to be utilized for crack propagation following the explosion.The specimens exhibited distinct failure patterns,resulting in corresponding changes in fractal dimensions.The simulated pore wall pressure–time curve validated the derived theoretical results,whereas the stress cloud map and explosion energy-time curve demonstrated the buffering effect of the water medium.As the water coupling coefficient increases,the buffering effect of the water medium becomes increasingly prominent. 展开更多
关键词 Water coupling coefficient Radial uncoupled charge Numerical simulation Fractal dimension
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Strong coupling and catenary field enhancement in the hybrid plasmonic metamaterial cavity and TMDC monolayers 被引量:1
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作者 Andergachew Mekonnen Berhe Khalil As’ham +2 位作者 Ibrahim Al-Ani Haroldo T.Hattori Andrey E.Miroshnichenko 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第5期20-32,共13页
Strong coupling between resonantly matched surface plasmons of metals and excitons of quantum emitters results in the formation of new plasmon-exciton hybridized energy states.In plasmon-exciton strong coupling,plasmo... Strong coupling between resonantly matched surface plasmons of metals and excitons of quantum emitters results in the formation of new plasmon-exciton hybridized energy states.In plasmon-exciton strong coupling,plasmonic nanocavities play a significant role due to their ability to confine light in an ultrasmall volume.Additionally,two-dimensional transition metal dichalcogenides(TMDCs) have a significant exciton binding energy and remain stable at ambient conditions,making them an excellent alternative for investigating light-matter interactions.As a result,strong plasmon-exciton coupling has been reported by introducing a single metallic cavity.However,single nanoparticles have lower spatial confinement of electromagnetic fields and limited tunability to match the excitonic resonance.Here,we introduce the concept of catenary-shaped optical fields induced by plasmonic metamaterial cavities to scale the strength of plasmon-exciton coupling.The demonstrated plasmon modes of metallic metamaterial cavities offer high confinement and tunability and can match with the excitons of TMDCs to exhibit a strong coupling regime by tuning either the size of the cavity gap or thickness.The calculated Rabi splitting of Au-MoSe_2 and Au-WSe_2 heterostructures strongly depends on the catenary-like field enhancement induced by the Au cavity,resulting in room-temperature Rabi splitting ranging between 77.86 and 320 me V.These plasmonic metamaterial cavities can pave the way for manipulating excitons in TMDCs and operating active nanophotonic devices at ambient temperature. 展开更多
关键词 catenary-shaped field enhancement strong coupling PLASMON EXCITON Rabi splitting
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Profile of Discordant Couples for Human Immunodeficiency Virus Infection Followed in Kinshasa: Case of Monkole Medical Center
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作者 Isaac T. Woto Cagod B. Inkale +3 位作者 Simplice K. Makoka Samclide Mbikayi Berry I. Bongenya Erick N. Kamangu 《World Journal of AIDS》 2023年第3期125-146,共22页
Background: Programs targeting serodiscordant couples in Africa are not a priority in efforts to prevent Human Immunodeficiency Virus (HIV) infection, although a large proportion of these occur in stable relationships... Background: Programs targeting serodiscordant couples in Africa are not a priority in efforts to prevent Human Immunodeficiency Virus (HIV) infection, although a large proportion of these occur in stable relationships, of which serodiscordance accounts for about two-thirds with a high risk of seroconversion of the seronegative partner. Objective: The objective of this study was to describe the profile of HIV serodiscordant couples followed in Kinshasa, DRC. Methods: Descriptive cross-sectional study to describe the profile of different heterosexual HIV serodiscordant couples followed at the Monkole Medical Center in Kinshasa, DRC, from November 2021 to June 2022. The data were collected from the information sheets elaborated by the research team as well as from the information provided by the computerized files of the patients managed at the Infectious Diseases Unit of the Monkole Medical Center after the signature of the informed consent. An average of 8 cc of blood was taken from a peripheral vein in the patient’s forearm, and was stored in EDTA tubes at −20˚C, of which at least 6 mL were used for biochemical analyses, 2 spots of 200 μL for each partner were stored on filter paper at −20˚C and were used for DNA extraction. Nested PCR confirmed the serological diagnosis. Results: Out of a total of 482 heterosexual couples followed for HIV at the Monkole Medical Center, 28 (5.8%) were HIV serodiscordant, of which 14 (2.9%) couples agreed to participate in the present study. The mean age was 43.39 ± 10 years with extremes ranging from 24 to 62 years. The patients were mainly from the informal sector (53.6%) and weighed between 61 and 71 kg (46.4%). Sexual intercourse continued in all couples, without condom use (85.7%) for desire of procreation (82.1%);although the great majority of HIV-negative partners (85.7%) were not under ARV prophylaxis. Leukopenia was found in 42.9% of HIV-negative partners compared to 21% of HIV-positive partners;all partners had a predominantly lymphocytic white blood cell count. 21.4% of HIV-negative partners had high HDL, 14.3% of HIV-positive partners had low HDL, and 14.3% of HIV-negative partners had high LDL. Chi-square and Pearson correlation tests showed no relationship between the biochemical parameters performed and the couples’ serodiscordance for HIV. Conclusion: The frequency of HIV discordant couples in Kinshasa is significant. Serodiscordance is encountered in young intellectual and entrepreneurial couples with a desire to procreate. It is desirable to carry out further analyses for better management of these couples. 展开更多
关键词 Discordant couple PROFILE HIV KINSHASA
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A semi-analytical model for coupled flow in stress-sensitive multi-scale shale reservoirs with fractal characteristics 被引量:1
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作者 Qian Zhang Wen-Dong Wang +4 位作者 Yu-Liang Su Wei Chen Zheng-Dong Lei Lei Li Yong-Mao Hao 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期327-342,共16页
A large number of nanopores and complex fracture structures in shale reservoirs results in multi-scale flow of oil. With the development of shale oil reservoirs, the permeability of multi-scale media undergoes changes... A large number of nanopores and complex fracture structures in shale reservoirs results in multi-scale flow of oil. With the development of shale oil reservoirs, the permeability of multi-scale media undergoes changes due to stress sensitivity, which plays a crucial role in controlling pressure propagation and oil flow. This paper proposes a multi-scale coupled flow mathematical model of matrix nanopores, induced fractures, and hydraulic fractures. In this model, the micro-scale effects of shale oil flow in fractal nanopores, fractal induced fracture network, and stress sensitivity of multi-scale media are considered. We solved the model iteratively using Pedrosa transform, semi-analytic Segmented Bessel function, Laplace transform. The results of this model exhibit good agreement with the numerical solution and field production data, confirming the high accuracy of the model. As well, the influence of stress sensitivity on permeability, pressure and production is analyzed. It is shown that the permeability and production decrease significantly when induced fractures are weakly supported. Closed induced fractures can inhibit interporosity flow in the stimulated reservoir volume (SRV). It has been shown in sensitivity analysis that hydraulic fractures are beneficial to early production, and induced fractures in SRV are beneficial to middle production. The model can characterize multi-scale flow characteristics of shale oil, providing theoretical guidance for rapid productivity evaluation. 展开更多
关键词 Multi-scale coupled flow Stress sensitivity Shale oil Micro-scale effect Fractal theory
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Factors Associated with Unmet Need for Family Planning among Couples Living in Urban and Rural Areas of Guinea in 2019
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作者 Soumah Aboubacar Fode Momo Conte Ibrahima +2 位作者 Bah Oumou Hawa Daniel William Athanass Leno Sy Telly 《Open Journal of Obstetrics and Gynecology》 2023年第6期1081-1093,共13页
Introduction: Unmet need for family planning (UNFP) is defined as women with unmet needs who want to stop or delay childbearing but are not using any method of contraception. The objective of this study was to analyze... Introduction: Unmet need for family planning (UNFP) is defined as women with unmet needs who want to stop or delay childbearing but are not using any method of contraception. The objective of this study was to analyze the factors associated with unmet needs for family planning among couples living in rural and urban areas of Guinea in 2019. Methodology: This was a prospective, analytical cross-sectional, multicenter study of a six-month period from August 1, 2018 to January 31, 2019, focusing on couples with unmet needs for family planning. Result: Among 189 couples interviewed, 567 had UNFP (33.3%), the reasons for not using modern contraceptive methods were desire for pregnancy (AOR = 2.74, 95% CI: 1.74, 4.31), husband’s refusal (AOR = 0.23, 95% CI: 0.06, 0.81), spousal attitude (AOR = 0.20, 95% CI: 0.130, 30), birth spacing (AOR = 2.10% to 95%: 1.16, 3.82), difficulty with a new pregnancy (AOR = 0.17, 95% CI: 0.04, 0.74), and spousal attitude (AOR = 0.20, 95% CI: 0.14, 0.30). Conclusion: The involvement of spouses, especially in rural communities, would help achieve family planning objectives and reduce unmet needs for family planning. 展开更多
关键词 Associated Factors Unmet Need Family Planning couplE RURAL URBAN GUINEA 2019
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Coupled multiphysical model for investigation of influence factors in the application of microbially induced calcite precipitation 被引量:1
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作者 Xuerui Wang Pavan Kumar Bhukya +1 位作者 Dali Naidu Arnepalli Shuang Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2232-2249,共18页
The study presents a comprehensive coupled thermo-bio-chemo-hydraulic(T-BCH)modeling framework for stabilizing soils using microbially induced calcite precipitation(MICP).The numerical model considers relevant multiph... The study presents a comprehensive coupled thermo-bio-chemo-hydraulic(T-BCH)modeling framework for stabilizing soils using microbially induced calcite precipitation(MICP).The numerical model considers relevant multiphysics involved in MICP,such as bacterial ureolytic activities,biochemical reactions,multiphase and multicomponent transport,and alteration of the porosity and permeability.The model incorporates multiphysical coupling effects through well-established constitutive relations that connect parameters and variables from different physical fields.It was implemented in the open-source finite element code OpenGeoSys(OGS),and a semi-staggered solution strategy was designed to solve the couplings,allowing for flexible model settings.Therefore,the developed model can be easily adapted to simulate MICP applications in different scenarios.The numerical model was employed to analyze the effect of various factors,including temperature,injection strategies,and application scales.Besides,a TBCH modeling study was conducted on the laboratory-scale domain to analyze the effects of temperature on urease activity and precipitated calcium carbonate.To understand the scale dependency of MICP treatment,a large-scale heterogeneous domain was subjected to variable biochemical injection strategies.The simulations conducted at the field-scale guided the selection of an injection strategy to achieve the desired type and amount of precipitation.Additionally,the study emphasized the potential of numerical models as reliable tools for optimizing future developments in field-scale MICP treatment.The present study demonstrates the potential of this numerical framework for designing and optimizing the MICP applications in laboratory-,prototype-,and field-scale scenarios. 展开更多
关键词 MULTIPHYSICS Microbially induced calcite precipitation(MICP) coupled thermo-bio-chemo-hydraulic(TBCH) model OpenGeoSys(OGS) Influence factors
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Algorithm Selection Method Based on Coupling Strength for Partitioned Analysis of Structure-Piezoelectric-Circuit Coupling
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作者 Daisuke Ishihara Naoto Takayama 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1237-1258,共22页
In this study, we propose an algorithm selection method based on coupling strength for the partitioned analysis ofstructure-piezoelectric-circuit coupling, which includes two types of coupling or inverse and direct pi... In this study, we propose an algorithm selection method based on coupling strength for the partitioned analysis ofstructure-piezoelectric-circuit coupling, which includes two types of coupling or inverse and direct piezoelectriccoupling and direct piezoelectric and circuit coupling. In the proposed method, implicit and explicit formulationsare used for strong and weak coupling, respectively. Three feasible partitioned algorithms are generated, namely(1) a strongly coupled algorithm that uses a fully implicit formulation for both types of coupling, (2) a weaklycoupled algorithm that uses a fully explicit formulation for both types of coupling, and (3) a partially stronglycoupled and partially weakly coupled algorithm that uses an implicit formulation and an explicit formulation forthe two types of coupling, respectively.Numerical examples using a piezoelectric energy harvester,which is a typicalstructure-piezoelectric-circuit coupling problem, demonstrate that the proposed method selects the most costeffectivealgorithm. 展开更多
关键词 MULTIPHYSICS coupling strength partitioned algorithm structure-piezoelectric-circuit coupling strongly coupled algorithm weakly coupled algorithm
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Risk behaviours associated with HIV and AIDS among couples in Rwamiko Sector, Gicumbi District, Rwanda
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作者 Jean Marie Vianney Tuyisenge Erigene Rutayisire 《Life Research》 2023年第3期59-65,共7页
Background:Risk behaviours have been linked to the spread of the Human Immunodeficiency Virus(HIV)epidemic in both urban and rural areas.Despite the progress made in the fight against HIV,it remains a public health co... Background:Risk behaviours have been linked to the spread of the Human Immunodeficiency Virus(HIV)epidemic in both urban and rural areas.Despite the progress made in the fight against HIV,it remains a public health concern worldwide.Risk behaviours such as not using condoms,having multiple sexual partners,and engaging in early sexual activity increase the risk of HIV infection.Therefore,it is important to assess these risk behaviours and understand the relationship between different factors and HIV,specifically among couples,in order to better understand the dynamics of the epidemic.The main objective of this study was to assess risk behaviours for HIV and AIDS among couples in Rwamiko sector,Gicumbi District,and suggest appropriate interventions for this group.Methods:This cross-sectional survey aimed to assess associated HIV and AIDS risk behaviours among couples in Rwamiko Sector,Gicumbi District,in order to determine the dynamics of the epidemic in this group and suggest appropriate interventions.Data was collected using a self-administered questionnaire and a multistage cluster random sampling technique.The collected data was then computed,analyzed,and presented in the form of tables and figures.Descriptive statistics were used to analyze all variables.Multivariate logistic regression was used to calculate odds ratios and 95%confidence intervals(CI)to investigate the relationship between the assessed factors,such as independent and dependent variables.The association between the studied factors was described using odds ratios with 95%CIs.Results:The majority of respondents were in the age group of 30-39 years.All respondents were married,and approximately 45%had completed primary education.The majority of respondents were unemployed.Respondents reported receiving HIV information from multiple sources,including radio,TV,films,school,church,health workers,parents,and friends.The findings of this study showed that some participants had knowledge about HIV transmission and prevention,while others did not.The proportion of respondents with a high level of HIV and AIDS knowledge was 30.61%(n=60),while moderate knowledge accounted for 53.57%(n=105).Furthermore,the proportion of respondents with a low level of knowledge on HIV and AIDS was 15.81%(n=31).The attitude towards HIV and AIDS was positive for 58.16%(n=114)of respondents,while 41.83%(n=82)had a negative attitude.None of the respondents reported using injection drugs.Significant associations were found between age(P-value=0.002,odds ratio(OR)=3.4,95%CI=1.59-7.67),gender(p=0.001,OR=2.6,95%CI=1.44-4.68),and alcohol consumption.There was also an association between age(P=0.001,OR=5.13,95%CI=2.04-12.91)and having multiple sexual partners.Conclusion:The majority of couples in Rwamiko Sector,Gicumbi District have a moderate level of knowledge and a positive attitude towards HIV and AIDS.However,the proportions of respondents with a low level of knowledge and a negative attitude should not be overlooked.The results of this study suggest the need to improve communication messages related to HIV,its transmission risks,and safer sexual behavior,particularly among couples in Rwamiko Sector,Gicumbi District. 展开更多
关键词 Risk Behaviour couples Rwamiko Sector Gicumbi District
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A review on electrocatalytic CO_(2) conversion via C-C and C-N coupling
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作者 Zhuangzhi Zhang Sijun Li +6 位作者 Zheng Zhang Zhou Chen Hua Wang Xianguang Meng Wenquan Cui Xiwei Qi Jiacheng Wang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第2期167-194,共28页
Electrochemical C-C and C-N coupling reactions with the conversion of abundant and inexpensive small molecules,such as CO_(2) and nitrogencontaining species,are considered a promising route for increasing the value of... Electrochemical C-C and C-N coupling reactions with the conversion of abundant and inexpensive small molecules,such as CO_(2) and nitrogencontaining species,are considered a promising route for increasing the value of CO_(2) reduction products.The development of high-performance catalysts is the key to the both electrocatalytic reactions.In this review,we present a systematic summary of the reaction systems for electrocatalytic CO_(2) reduction,along with the coupling mechanisms of C-C and C-N bonds over outstanding electrocatalytic materials recently developed.The key intermediate species and reaction pathways related to the coupling as well as the catalyst-structure relationship will be also discussed,aiming to provide insights and guidance for designing efficient CO_(2) reduction systems. 展开更多
关键词 C-C coupling C-N coupling CO_(2) conversion ELECTROCATALYSIS urea synthesis
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Analysis of Strong Coupling Constant with Machine Learning and Its Application
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作者 王晓云 董晨 刘翔 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第3期15-22,共8页
We investigate the nature of the strong coupling constant and related physics.Through the analysis of accumulated experimental data around the world,we employ the ability of machine learning to unravel its physical la... We investigate the nature of the strong coupling constant and related physics.Through the analysis of accumulated experimental data around the world,we employ the ability of machine learning to unravel its physical laws.The result of our efforts is a formula that captures the expansive panorama of the distribution of the strong coupling constant across the entire energy range. 展开更多
关键词 STRONG couplING accumulated
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Nonlinearly induced entanglement in dissipatively coupled optomechanical system
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作者 杨文全 冷轩 +1 位作者 程泂 张闻钊 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期255-260,共6页
Nonlinearly induced steady-state photon–phonon entanglement of a dissipative coupled system is studied in the bistable regime. Quantum dynamical characteristics are analysed by solving the mean-field and fluctuation ... Nonlinearly induced steady-state photon–phonon entanglement of a dissipative coupled system is studied in the bistable regime. Quantum dynamical characteristics are analysed by solving the mean-field and fluctuation equations of the system. It is shown that dissipative coupling can induce bistable behaviour for the effective dissipation of the system.Under suitable parameters, one of the steady states significantly reduces the dissipative effect of the system. Consequently,a larger steady-state entanglement can be achieved compared to linear dynamics. Furthermore, the experimental feasibility of the parameters is analysed. Our results provide a new perspective for the implementation of steady-state optomechanical entanglement. 展开更多
关键词 ENTANGLEMENT optomechanical system dissipatively coupling
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Seismic performance evaluation of hybrid coupled shear wall system with shear and flexural fuse-type steel coupling beams
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作者 Zahra Ramezandoust Abbas Tajaddini Panam Zarfam 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第3期691-712,共22页
Replaceable flexural and shear fuse-type coupling beams are used in hybrid coupled shear wall(HCSW)systems,enabling concrete buildings to be promptly recovered after severe earthquakes.This study aimed to analytically... Replaceable flexural and shear fuse-type coupling beams are used in hybrid coupled shear wall(HCSW)systems,enabling concrete buildings to be promptly recovered after severe earthquakes.This study aimed to analytically evaluate the seismic behavior of flexural and shear fuse beams situated in short-,medium-and high-rise RC buildings that have HCSWs.Three building groups hypothetically located in a high seismic hazard zone were studied.A series of 2D nonlinear time history analyses was accomplished in OpenSees,using the ground motion records scaled at the design basis earthquake level.It was found that the effectiveness of fuses in HCSWs depends on various factors such as size and scale of the building,allowable rotation value,inter-story drift ratio,residual drift quantity,energy dissipation value of the fuses,etc.The results show that shear fuses better meet the requirements of rotations and drifts.In contrast,flexural fuses dissipate more energy,but their sectional stiffness should increase to meet other requirements.It was concluded that adoption of proper fuses depends on the overall scale of the building and on how associated factors are considered. 展开更多
关键词 hybrid coupled shear wall steel fuse coupling beam shear and flexural fuse nonlinear dynamic analysis seismic performance
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Chimera states of phase oscillator populations with nonlocal higher-order couplings
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作者 伍勇刚 余华健 +1 位作者 郑志刚 徐灿 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期402-407,共6页
The chimera states underlying many realistic dynamical processes have attracted ample attention in the area of dynamical systems.Here, we generalize the Kuramoto model with nonlocal coupling incorporating higher-order... The chimera states underlying many realistic dynamical processes have attracted ample attention in the area of dynamical systems.Here, we generalize the Kuramoto model with nonlocal coupling incorporating higher-order interactions encoded with simplicial complexes.Previous works have shown that higher-order interactions promote coherent states.However, we uncover the fact that the introduced higher-order couplings can significantly enhance the emergence of the incoherent state.Remarkably, we identify that the chimera states arise as a result of multi-attractors in dynamic states.Importantly, we review that the increasing higher-order interactions can significantly shape the emergent probability of chimera states.All the observed results can be well described in terms of the dimension reduction method.This study is a step forward in highlighting the importance of nonlocal higher-order couplings, which might provide control strategies for the occurrence of spatial-temporal patterns in networked systems. 展开更多
关键词 synchronization complex system coupled oscillators phase transition
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Effects of asymmetric coupling and boundary on the dynamic behaviors of a random nearest neighbor coupled system
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作者 徐玲 姜磊 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期309-322,共14页
This study investigates the dynamical behaviors of nearest neighbor asymmetric coupled systems in a confined space.First, the study derivative analytical stability and synchronization conditions for the asymmetrically... This study investigates the dynamical behaviors of nearest neighbor asymmetric coupled systems in a confined space.First, the study derivative analytical stability and synchronization conditions for the asymmetrically coupled system in an unconfined space, which are then validated through numerical simulations. Simulation results show that asymmetric coupling has a significant impact on synchronization conditions. Moreover, it is observed that irrespective of whether the system is confined, an increase in coupling asymmetry leads to a hastened synchronization pace. Additionally, the study examines the effects of boundaries on the system's collective behaviors via numerical experiments. The presence of boundaries ensures the system's stability and synchronization, and reducing these boundaries can expedite the synchronization process and amplify its effects. Finally, the study reveals that the system's output amplitude exhibits stochastic resonance as the confined boundary size increases. 展开更多
关键词 asymmetric coupled confined space SYNCHRONIZATION stochastic resonance stability
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Research on modeling and self-excited vibration mechanism in magnetic levitation-collision interface coupling system
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作者 Jinghu TANG Chaofeng LI +1 位作者 Jin ZHOU Zhiwei WU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第5期873-890,共18页
The modeling and self-excited vibration mechanism in the magnetic levitation-collision interface coupling system are investigated.The effects of the control and interface parameters on the system's stability are a... The modeling and self-excited vibration mechanism in the magnetic levitation-collision interface coupling system are investigated.The effects of the control and interface parameters on the system's stability are analyzed.The frequency range of self-excited vibrations is investigated from the energy point of view.The phenomenon of self-excited vibrations is elaborated with the phase trajectory.The corresponding control strategies are briefly analyzed with respect to the vibration mechanism.The results show that when the levitation objects collide with the mechanical interface,the system's vibration frequency becomes larger with the decrease in the collision gap;when the vibration frequency exceeds the critical frequency,the electromagnetic system continues to provide energy to the system,and the collision interface continuously dissipates energy so that the system enters the self-excited vibration state. 展开更多
关键词 magnetic levitation coupling system self-excited vibration mechanical interface vibration frequency
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Response analysis of NMRG system considering Rb-Xe coupling
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作者 Yi Zhang Qiyuan Jiang +6 位作者 Bingfeng Sun Jiahu Wei Lin Yang Yongyuan Li Zhiguo Wang Kaiyong Yang Hui Luo 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期390-402,共13页
The dynamic range of the nuclear magnetic resonance gyroscope can be effectively improved through the closedloop control scheme,which is crucial to its application in inertial measurement.This paper presents the analy... The dynamic range of the nuclear magnetic resonance gyroscope can be effectively improved through the closedloop control scheme,which is crucial to its application in inertial measurement.This paper presents the analytical transfer function of Xe closed-loop system in the nuclear magnetic resonance gyroscope considering Rb–Xe coupling effect.It not only considers the dynamic characteristics of the system more comprehensively,but also adds the influence of the practical filters in the gyro signal processing system,which can obtain the accurate response characteristics of signal frequency and amplitude at the same time.The numerical results are compared with an experimentally verified simulation program,which indicate great agreement.The research results of this paper are of great significance to the practical application and development of the nuclear magnetic resonance gyroscope. 展开更多
关键词 NUCLEAR magnetic RESONANCE GYROSCOPE transfer characteristics Rb–Xe couplING
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Customized modulation on plasma uniformity by non-uniform magnetic field in capacitively coupled plasma
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作者 王森 张权治 +2 位作者 马方方 Maksudbek YUSUPOV 王友年 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第6期79-87,共9页
A two-dimensional fluid model based on COMSOL Multiphysics is developed to investigate the modulation of static magnetic field on plasma homogeneity in a capacitively coupled plasma(CCP)chamber. To generate a static m... A two-dimensional fluid model based on COMSOL Multiphysics is developed to investigate the modulation of static magnetic field on plasma homogeneity in a capacitively coupled plasma(CCP)chamber. To generate a static magnetic field, direct current is applied to a circular coil located at the top of the chamber. By adjusting the magnetic field's configuration, which is done by altering the coil current and position, both the plasma uniformity and density can be significantly modulated. In the absence of the magnetic field, the plasma density exhibits an inhomogeneous distribution characterized by higher values at the plasma edge and lower values at the center. The introduction of a magnetic field generated by coils results in a significant increase in electron density near the coils. Furthermore, an increase in the sets of coils improves the uniformity of the plasma. By flexibly adjusting the positions of the coils and the applied current,a substantial enhancement in overall uniformity can be achieved. These findings demonstrate the feasibility of using this method for achieving uniform plasma densities in industrial applications. 展开更多
关键词 COMSOL capacitively coupled plasma plasma uniformity magnetic field
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Study on synergistic leaching of potassium and phosphorus from potassium feldspar and solid waste phosphogypsum via coupling reactions
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作者 Chao Li Shizhao Wang +3 位作者 Yunshan Wang Xuebin An Gang Yang Yong Sun 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期117-129,共13页
To achieve the resource utilization of solid waste phosphogypsum(PG)and tackle the problem of utilizing potassium feldspar(PF),a coupled synergistic process between PG and PF is proposed in this paper.The study invest... To achieve the resource utilization of solid waste phosphogypsum(PG)and tackle the problem of utilizing potassium feldspar(PF),a coupled synergistic process between PG and PF is proposed in this paper.The study investigates the features of P and F in PG,and explores the decomposition of PF using hydrofluoric acid(HF)in the sulfuric acid system for K leaching and leaching of P and F in PG.The impact factors such as sulfuric acid concentration,reaction temperature,reaction time,material ratio(PG/PF),liquid–solid ratio,PF particle size,and PF calcination temperature on the leaching of P and K is systematically investigated in this paper.The results show that under optimal conditions,the leaching rate of K and P reach more than 93%and 96%,respectively.Kinetics study using shrinking core model(SCM)indicates two significant stages with internal diffusion predominantly controlling the leaching of K.The apparent activation energies of these two stages are 11.92 kJ·mol^(-1)and 11.55 kJ·mol^(-1),respectively. 展开更多
关键词 PHOSPHOGYPSUM Potassium feldspar coupling reaction LEACHING Waste treatment Kinetics
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Dynamic Coupling Analysis of Semisubmersible Platform Float-over Method for Docking Case
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作者 DING Hongyan QIN Licheng +2 位作者 ZHANG Puyang SONG Zhengrong XIE Weiwei 《Journal of Ocean University of China》 CAS CSCD 2024年第2期345-357,共13页
In this paper,the multi-body coupled dynamic characteristics of a semisubmersible platform and an HYSY 229 barge were investigated.First,coupled hydrodynamic analysis of the HYSY 229 barge and the semisubmersible plat... In this paper,the multi-body coupled dynamic characteristics of a semisubmersible platform and an HYSY 229 barge were investigated.First,coupled hydrodynamic analysis of the HYSY 229 barge and the semisubmersible platform was performed.Relevant hydrodynamic parameters were obtained using the retardation function method of three-dimensional frequency-domain potential flow theory.The results of the hydrodynamic analysis were highly consistent with the test findings,verifying the accuracy of the multifloating hydrodynamic coupling analysis,and key hydrodynamic parameters were solved for different water depths and the coupling effect.According to the obtained results,the hydrodynamic influence was the largest in shallow waters when the coupling effect was considered.Furthermore,the coupled motion equation combined with viscous damping,fender system,and mooring system was established,and the hydrodynamics,floating body motion,and dynamic response of the fender system were analyzed.Motion analysis revealed good agreement among the surge,sway,and yaw motions of the two floating bodies.However,when the wave period reached 10 s,the motion of the two floating bodies showed severe shock,and a relative motion was also observed.Therefore,excessive constraints should be added between the two floating bodies during construction to ensure construction safety.The numerical analysis and model test results of the semisubmersible platform and HYSY 229 barge at a water depth of 42 m and sea conditions of 0°,45°,and 90° were in good agreement,and the error was less than 5%.The maximum movement of the HYSY 229 barge reached 2.61 m in the sway direction,whereas that of the semisubmersible platform was 2.11 m.During construction,excessive constraints should be added between the two floating bodies to limit their relative movement and ensure construction safety. 展开更多
关键词 float-over method semisubmersible platform coupling hydrodynamic fender system time-domain analysis
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